Mechanical properties of recently developed Si{sub}3N{sub}4-SiC nanocomposite

摘要

Some mechanical properties (bending strength, hardness and fracture toughness) have been investigated in order to reveal the effect of adding carbon and silica to Si{sub}3N{sub}4. The low value of bending strength indicated the presence of some defects in the material. Scanning electron microscopy revealed that fracture in the Si{sub}3N{sub}4/SiC nanocomposite always originated from carbon agglomerates. These agglomerates caused a significant strength reduction of the studied material. The high value of Weibull modulus of the specimens indicates the same kind of defects with a similar size, geometry and location.